1. Field of the Invention
The present invention relates to medical retractors.
2. Background Information
Medical retractors are used to retract tissue and bone of a patient. For example, when performing open heart surgery a surgeon will utilize a retractor to pull apart the rib cage of a patient.
FIGS. 1 and 2 show a retractor 1 of the prior art. The retractor 1 includes a pair of blades 2 and 3 attached to corresponding arms 4 and 5, respectively. Arm 4 is coupled to a rack and pinion gear assembly 6 that allows one blade 2 to move relative to the other blade 3. The pinion is connected to a handle 7 that can be rotated by the surgeon to move the blade 2 and retract tissue and bone.
The amount of spreading is typically controlled by the force applied by the surgeon to the retractor handle 7 and may be estimated by the manual xe2x80x9cfeelxe2x80x9d of the retractor""s resistance to handle rotation. Excessive retractor forces may crack or bruise bone, strain supporting cartilage and otherwise cause damage to the patient. This damage increases the amount of post-operative pain and recovery time for the patient. It would be desirable to provide a retractor that would allow the surgeon to more accurately control the amount of force applied to a patient.
A retractor that includes a first blade, a second blade and a gear assembly coupled to the second blade. The retractor also has a torque measuring device, force measuring device and/or slip clutch that allows a surgeon to control the application of force by the retractor.